Patent Document 1 (Japanese Patent Application Laid-open (JP-A) No. 2004-009975) discloses a door structure for a vehicle side portion that does not have a center pillar. In order to improve safety at the time of a side impact, the door structure has a reinforcement that covers, from the vehicle outer side, three door locks provided in a vehicle vertical direction upper portion, middle portion, and lower portion of the door structure. In this door structure, a side impact load is dispersed in the vertical direction by the reinforcement.
Examples of configurations where, in a door structure for a vehicle side portion that does not have a center pillar, lock mechanisms are provided in the vehicle vertical direction upper portion, middle portion, and lower portion of the door structure include those disclosed in patent document 2 (JP-A No. 2004-090670) and patent document 3 (JP-A No. 2004-027811).
Considering a side impact between a barrier and a vehicle, depending on the position of the bumper of the barrier it is easy for the impact load to be input to the lock member in the vertical direction lower portion of the vehicle. However, in the door structure disclosed in patent document 1 (JP-A No. 2004-009975), there is room for improvement in terms of improving safety performance at the time of a side impact by effectively protecting the lock member disposed in the vehicle vertical direction lower portion.